There is known in general in the prior art a number of methods for protecting the contents of a container through the use of a reclosable closure. More particularly, these types of closure systems are adapted for potato chip bags, cereal bags, bread bags, or the like, and usually the bag itself is a plastic or coated paper system which is flexible and may easily be twisted or manipulated; and for rigid containers such as cereal and detergent boxes.
One of the most widely used methods for resealing or reclosing a flexible container involves a use of a separate component such as a metal wire twist tie which is covered with paper, or a plastic clip. These are typical methods for closing a loaf of bread. These methods, however, have several disadvantages due to the fact that the reclosable seals are not part of the container. The plastic clips or twist ties may often be misplaced between uses and also require some degree of fine motor control, therefor making their use difficult for the young, elderly, and the physically handicapped. Additionally, after repeated use, plastic clips often break and the twist ties expose their metal wires making their use potentially hazardous. These closures may also pose a risk of choking or other hazards for small children who may have access to them. These types of closures can also cause tears in the container.
Another known construction utilizes zip lock.RTM., and similar zipper-like sealing means to provide the containers with the reclosable air tight seal. This construction adds substantially to the cost of the container and adds difficulty to its manufacture. Furthermore, these systems also require some fine motor control which may prove difficult again for the young, elderly or physically handicapped.
Previous attempts at developing reclosable sealing means involving pressure sensitive adhesives were largely unsuccessful or unnecessarily complex. Many resealable systems were unreliable in that after a limited number of reclosures, the seal would often fail to further adhere, or in other words, the pressure sensitive adhesive would lose its tack. Other systems require components which had to be manufactured using methods of die cutting or other off line processes thereby prohibitively raising the cost thereof.
One example of a reclosing system is shown in U.S. Pat. No. 4,552,269, which discloses a resealable device consisting of a paper or foil blank in a sealing flap. While this is an improvement over prior resealable devices, this device still requires production through die cutting means and provides only a limited size opening which can be resealed. Another system is shown in U.S. Pat. No. 4,584,201, which shows use of an adhesive strip positioned parallel to a top sealed edge of the bag. The top edge can be folded upon itself and then adhered to the strip to effect a closure.
One other closure system after which the instant invention is designed but is believed to represent an improvement thereover, is that shown in patent application Ser. No. 413,951, filed Sept. 28, 1989, by Kurt M. Schramer, for "A Reclosable Flexible Container and Method of Reclosing". The instant system is believed to represent an improvement thereover, because it is simpler to manufacture and apply, it allows advertisement as well as instructions for use associated with the closure throughout its useful life so as to give good promotional and use characteristics, and it is simple and effective to use.